Double-tube tire.



No.7'72,758. I PATENTED 0CT.18,1904.

F. F. THOMPSON.

DOUBLE TUBE TIRE. APPLICATION FILED JULY 23. 1904.

NOMODEL.

WITNESSES: nvmvme 15 @QMAW FmdzMJ i Thompson By '-1 I ATTORNEYS UNITEDST TES Patented October 18, 1904.

PATENT OFFICE.

DOUBLE-TUBE TIRE.

SPECIFICATION forming part of Letters Patent N0. 772,758, dated October18, 1904. Application filed July 23, 1904.. Serial No. 217,795. (Nomodel.)

To all whom-it may concern.

Be it known that I, FR-EDRIOK' FOSTER THOMPSON, a citizen ofthe UnitedStates, residing at Lawton, in the county of Comanche,

Oklahoma Territory, haveinvented anew and useful Improvement inDouble-Tube Tires, of which the following is a specification.

My invention relates to double-tube tires for bicycles, automobiles, andother vehicles. In the M and W tire and others of its class the heavierouter tube is slitted longitudinally on the inner side neXt the rim fora distance of about five inches, and at the end of the slit andcommunicating with the same is a round hole to receive the valve-nippleof the inner tube, whichprotrudes through the hole, the two edges of theslit being afterward laced together up to thevalve-nipple. In thisarrangement the. valve-nipple holein the outer tube really forms the endof the slit, and the hole is not surrounded by an unbroken collar of theouter tube material, but is open or slitted at one side. the inner tubeit has been found that the expansion ofthe inner tube at the point ofjuncture of the hole and the slit will allow the edges of the slit toexpand on this side of the valve no matter how tightly laced, and thisproduces several objectionable results. In the first place it causes abulge onthe inner surface of the tire on that side of the valve whichwill not let the tire fit up close and solid to the rim and which as thewheel revolves allows the valve-nipple to have a movement through thehole in the rim, in and out, which rubbing and chafing action causes thevalve-nipple to rapidly wear and become leaky. In the second place thisbulge on one side of the valve turns the valve-nipple from its trueradial position to a position inclined to the radial, which acceleratesits wear and depreciation. In the third place the strain of the bulgingof the inner tube at this point comes upon the lacing and tears out thelacing-holes on each side of the slit adjacent to the valve. Myinvention is designed to overcome all of thesedifliculties in a simpleand In inflating practical way; and to that end it consists in locatingthe valve-hole of the outer tire at a distance beyondthe slit, so thatsaid hole is not bisected on one side by the slit; but the hole has asolid collar of the outer tube material all around the valve-hole,forming an unbroken reinforce for the valve-nipple, so that there is nobulging ofv the inner tube on one side of the valve immediately adjacentthereto and the above-named difficulties are en tirely obviated.

Figure 1 is a perspective view of a portion ofmy improved double-tubetire. Fig. l is a longitudinal section, and Fig. 2'is a view of aportion of the old form of double-tube tire.

In Figs. land 1.? A is the outer tube; B,

the inner tube bearing the valve-nipple C.

D is the longitudinal lacing slit, d the lacing, and E the hole toreceive theextension of the valve-nipple therethrough. This hole, itwill be seen, does not form the end of the slit, as

seen in Fig. '2, but is located about an inch beyond the end of theslit, so that there is an unbroken reinforce of the material of theouter tube all around the hole E. This allows the inner face of theouter tube to fit up flush to the face of the rim, maintains the nipplein true radial position, and avoids the spreading of the slit and thetearing out of the lacing-holes immediately adjacent to the valve. i

To insert the inner tube bearing the valve into the outer tube, this isdone in much the same manner as heretofore, except that in drawing inthe inner tube the lower part of the valve is drawn past the hole Euntil the free end of the valve is even with the hole, and then theinner tube is drawn back and the free endof thevalve is allowed toprotrude outwardly through the hole. In this way it may be easilyinserted orremoved.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. A double-tube tire, comprising an inner tube with-valve-nipple and anouter tube hav: ing a longitudinal slit in its inner face and avalve-hole placed beyond the end of the slit and surrounded by an uncutring of the outer tube material substantially as described.

2. A double-tube tire comprising an inner tube with valve-nipple, anouter tube having 5 a longitudinal slit in its inner face and avalvehole placed beyond the end of the slit and surrounded by the uncutring of the outer tube material and a lacing for closing the slitsubstantially as shown and described.

FREDRICK FOSTER THOMPSON.

Witnesses:

J. A. ANDERSON, E. R. lvloDurrnr.

